مهندسی مکانیک مدرس

مهندسی مکانیک مدرس

مطالعه عددی تبخیر در یک کانال متخلخل قائم با روش حجم سیال در اپن‌فوم

نوع مقاله : پژوهشی اصیل

نویسندگان
1 گروه تبدیل انرژی، دانشکده مهندسی مکانیک، دانشگاه گیلان، رشت، ایران
2 گروه علوم مهندسی، دانشکده فنی مهندسی شرق گیلان، دانشگاه گیلان، رودسر، ایران
چکیده
در مطالعه حاضر با روش حجم سیال در نرم‌افزار متن‌باز اپن‌فوم پدیده تبخیر در محیط متخلخل مورد تحلیل قرار گرفته است. در ابتدای حل، سیستم شامل فاز آب و محیط متخلخل مس است. در مراحل بعدی شبیه‌سازی عددی و در اثر تبخیر قسمتی از آب، فاز بخار به‌عنوان دومین فاز سیال ظاهر می‌شود. آب و بخار، غیرقابل تراکم و مخلوط‌نشدنی فرض شده است و پدیده تبخیر به‌صورت غیرتعادلی رخ می‌دهد. فصل مشترک بین فازها با روش حجم سیال، انتقال جرم بین دو فاز آب و بخار با مدل لی و کشش سطحی بین فازها با روش نیروی سطح پیوسته مدل‌سازی شده است. مقایسه نتایج شبیه‌سازی با نتایج تجربی نشان داد که حلگر ترکیبی تبخیر محیط متخلخل به‌خوبی نرخ تبخیر در مقاطع مختلف کانال را تخمین می‌زند. علاوه بر این نتایج مربوط به دمای دیواره به دو ناحیه گرمایشی و تبخیر تقسیم می‌شود. در ناحیه گرمایش، دما به‌طور خطی با عمق کانال افزایش می‌یابد تا اینکه به دمای اشباع برسد. بعد از نقطه اشباع دمای دیواره ابتدا ثابت مانده و در نهایت شکل نوسانی به خود می‌گیرد که به‌صورت محلی، پرش‌های دمایی رخ می‌دهد. نرخ جرمی تولید بخار نیز ابتدا با شدت زیاد اتفاق می‌افتد اما در نواحی انتهایی کانال متخلخل، نرخ رشد آن به‌کندی صورت می‌گیرد.
کلیدواژه‌ها

موضوعات


عنوان مقاله English

Numerical Study of Evaporation in a Vertical Porous Channel By the volume of fluid method in OpenFOAM

نویسندگان English

H. Gholami 1
R. Kouhikamali 1
N. Sharifi 2
1 Energy Conversion Department, Mechanical Engineering Faculty, University of Guilan, Rasht, Iran
2 Engineering Sciences Department, Engineering Faculty (East Guilan), University of Guilan, Rudsar, Iran
چکیده English

In this study, using volume of fluid method in open source software OpenFOAM, the phenomenon of evaporation in the porous medium was analyzed. At the beginning of the solution, the system consists of a water phase and a porous copper environment. In the next steps of numerical simulation and as a result of partial evaporation of water, the vapor phase appears as the second fluid phase. Water and vapor are assumed to be incompressible and incompatible, and the phenomenon of evaporation occurs unevenly. The interface between phases is modeled by the VOF method and the Lee model has been used to mass transfer between two phases of water and vapor. For surface tension between phases, the continuous surface force (CSF) method was considered. The comparison of simulation results with experimental results showed that the combined solver of porous medium evaporation would well estimate the rate of evaporation at different sections of the channel. In addition, the results of the wall temperature indicate that the channel is divided into two zones of heating and evaporation. In the region of heating, the temperature increases linearly with the channel length to reach saturation temperature. After the point of saturation, the wall temperature first remains constant and eventually forms an oscillatory shape, in which locally there are temperature jumps. The evaporated flow rate also increases at high intensity first, but in the end regions of the porous channel, its growth rate is slow.

کلیدواژه‌ها English

evaporation
Porous Medium
Vertical channel
Volume of Fluid Method
OpenFoam software
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